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I plan on driving my truck to Chris next week sometime. Do I have to do a crank relearn after the new performance mods are installed? With the dealer? Or is this something that he is capable of doing in house? Maybe I should just ask Chris!

You do not have to worry about doing a crank relearn if you are driving your vehicle to Chris. All he needs is about 5-1o mins with your truck to plug in to the underdash connector and you'll be tearing up the streets.

The only time you need a crank relearn is if you send in your cores and they send you a different set of cores. As long as the cores you get tuned are the ones that came with your truck, no relearn is required.

To the guys that have gotten a spare set for services runs to the dealer...what did you tell them when you needed a crank relearn? I'm thinking they are going to be like....."why do you need a crank relearn, it's a new truck..."?

Also, I just want to make sure that the mileage is not stored on the ecm or tcm.

I took the dumba** approach at the dealer....I called OnStar, told the operator "hey, I got a check engine light glowing on my dash...what's that mean?" OnStar did a remote vehicle diagnostic, told me what it was (crank variation problem) and the code number: PO315.

Then I got OnStar to direct me to the nearest Chevy dealer, pulled in there, and told the service manager "hey, OnStar told me to get to a dealer quickly...I've got a PO315 error code!".

The service writer looked it up, grabbed his scanner and hooked it up to the underdash plug, followed the scanner prompts, and the light went out.

Took all of 15 minutes...asked what I owed, he said, "forget it". Gave him $20 for lunch, and was on my way.

I got the guy's name before I left, and sent a glowing thanks to GM about this guy via their customer service website. That must have been a good idea, because the service writer sent ME a thanks e-mail a couple of days later.

I've had MUCH better luck with Chevy dealers in small towns for things like this. Dealers in larger cities are all about volume, and they rarely want to fiddle with little things that don't make them a lot of money. I didn't mention it in the first post, but before I found the small dealer, I went to a dealer in a large town. That stud wanted $199 just to hook the scanner to the truck!

Small town dealers are....dare I say it...interested in keeping customers happy.

Also, Chris and Kirk at Vector often have contacts at dealers in several areas. They gave me the name of a Cadillac dealer that could do the relearn - Chris even called the Caddy guy to tell him I was coming. But I tried the dumba** approach first, and was successful.

I'm glad you guys are finding this useful I hope to provide many more useful write-ups

Since you took the time to create this thread and take pictures, the least I could do is say, Thank you very much!

I was putting off a VM tune simply because I was nervous about removing the ECM/TCM. Your instruction and pictures made all the difference. Like you said, its a simple 3-5 minute job, when you know what to do.

Your taking the time to help other SS owners is what good forums like this one is all about!

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